Officers investigating the theft of gold coins worth more than £30,000 are appealing for information to help trace them.

The coin bearing the name of Sponsian was considered apocryphal and had been locked away in a museum cupboard.

Police are looking for a man who used a counterfeit $50 coin to make a purchase at an Urbandale gas station in February. The gold-colored coin, featuring two eagles and inscribed with the words "1 OZ.

The force said 10 gold Britannia bullion coins - each weighing 1oz (about 31.1g) - and another 10 of the same coins weighing 0.25oz (about 7.8g) - were stolen.